Rotary relay



March 13, 1928. 1,662,677

0. JENKINS ROTARY RELAY FiledJuly 2.1, 1924 Patented Mar. 13, 1928. i

' UNITED STATES PATENT'OFFICE.

CHARLES FRANCIS JENKINS, OF WASHINGTON, DISTRICT OF COLUMBIA ROTARYRELAY.

Application filed July 21, E24. Serial No. 727,271.

result the motor D will presently fall into step with the incoming radiocurrent frequency and continue to run at that speed.

But the motor E continues to lag until contact piece I catches up withcontact piece H, and the resistance G is momentarily cut out, whereupon,the motor speed increasing,

This invention relates to devices for controlling the speed of distantmotors, and has for its particular object means for controlling motorspeeds by radio. 7 a With this and other objects in view the inventionconsists in the novel details of construction and combinations of parts.more fully hereinafter disclosed and particularly pointed out in theclaims. down again.

Referring to the accompanying drawing, This cycle is repeatedindefinitely, but as which is,a schematic drawing of the device, thelagging to close the shortcircuit through A is a radio antenna; B aground; andC a receiving set; and C an amplifier. D is a miniature,synchronous motor takin current from the amplifier set; D a pinlon onthe. motor shaft, engaging with a larger gear D E is the'power motor itis desired to control {F the current supply therefor; G *an adjustableresistance in circuit with the motor and power supply. On the shaft ofthe large motor and the jack shaft of the small motor are contactingdogs H and I insulated from their respective shafts, and having brushesK and M in contact with the hubs of each. These brushes are in a circuitwhich cuts out ,all or part of the What I claim, isresistance G. N is ashortcii'cuiting push 1. In combination, a power motor, a conbutton. Ris a radio photo camera which trol motor, a rotatable contact member hasco-acting therewith the lamp S, electridriven by said control motor at adefinite call in circuit with the amplifier 0. 'speed, a secondrotatable contact member The operation of the device is as followsdriven by the power motor in the path of Let it be assumed that theradio set is the first contact member and at a lower receiving signalswith a given frequencyffor speed ,than the first, said contact membersexample, 540 cycles, the frequency often em co-acting when engaged'to.close a circuit to ployed in radio photographyby applicant. cause-saidpowermotor to increase-its speed,

If then the circuit is closed through the and means independent of saidcont-act memmotor E, the resistance G and the current has for closingsaid circuit;

1 supply F, the motorE will rotate. and be- 2. In a device of thecharacter described,

cause the'dog I- pushes the dog 'H around, I

40 the rotorof motor D 'will'be dragged around,

- but at a s ed below-thespeed necessary to get it in step with theincoming radio ei als. i i

ehfhowever, the shortcircuitingpushbutton such a small decrement andincrement respcctively, the lack of steadiness in the rotation of themotor E can not be detected.

From the amplifier current is put through the lamp S, and, as thecurrent is a modulated current, the intensity of the light varies withthe variation in the strength of the current. The radio-carried currenthas a constant frequency (5 10 perhaps) but having a modulatedcharacter, this latter characteristic can be usefull employed tofluctuate the intensity of t e light S, the one 25 electric-currentserving the two purposes.

0nd motor, a contact member on said second tation of said firstmentionedcontact member, and a current supply controlled by Said switch N isclosed the motor E speeds contact members. 7 up until the small motor Dis runnin fast- 3. In combinatlon, a power motor, a con- 7 er thannormal. If now the button be retrol motor, a rotatable vcontact memberleased the motor E will slow down because. driven by each motor, saidcontact members of the resistancenow in the circuit. its a co-acting toclose a clrcuit control the the combinationof a synchronous motor, acontact member rotated by said motor, a secthe contact is broken and themotor slows M I H K and the acceleration to open it is motor located tointerfere with the free roj speed of the power motor, and meansindependent of said contact members for closing said circuit.

4. In combination, a power motor, a control motor, mechanical meansconnecting said motors comprising two co-acting ele ments having limiteddifl'erential movement for initiating the operation of the control motorby the power motor, and means responslve to-difierential movementbetween 10 said elements for controlling the speed of thepower motor.

In testimony whereof I have aflixed my signature.

CHARLES FRANCIS JENKINS.

